Fix resource generation script (#1197)

Author: NicolasHug

.github/workflows/reference_resources.yaml

@@ -55,10 +55,9 @@ jobs:
         python-version: ['3.10']
         ffmpeg-version-for-tests: ['4.4.2', '5.1.2', '6.1.1', '7.0.1']
     steps:
-      - uses: actions/download-artifact@v4
-        with:
-          name: meta-pytorch_torchcodec__${{ matrix.python-version }}_cpu_x86_64
-          path: pytorch/torchcodec/dist/
+      - name: Check out repo
+        uses: actions/checkout@v3
+
       - name: Setup conda env
         uses: conda-incubator/setup-miniconda@v2
         with:
@@ -67,28 +66,25 @@ jobs:
           activate-environment: test
           python-version: ${{ matrix.python-version }}
 
-      - name: Install ffmpeg
-        run: |
-          conda install "ffmpeg=${{ matrix.ffmpeg-version-for-tests }}" -c conda-forge
-          ffmpeg -version
-
       - name: Update pip
         run: python -m pip install --upgrade pip
 
-      - name: Install generation dependencies
-        run: |
-          # Note that we're installing stable - this is for running a script where we're a normal PyTorch
-          # user, not for building TorhCodec.
-          python -m pip install torch --index-url https://download.pytorch.org/whl/cpu
-          python -m pip install numpy pillow pytest
+      - name: Install PyTorch
+        run: bash packaging/install_pytorch.sh cpu "torch"
+
+      - uses: actions/download-artifact@v4
+        with:
+          name: meta-pytorch_torchcodec__${{ matrix.python-version }}_cpu_x86_64
+          path: dist/
 
       - name: Install torchcodec from the wheel
-        run: |
-          wheel_path=`find pytorch/torchcodec/dist -type f -name "*.whl"`
-          echo Installing $wheel_path
-          python -m pip install $wheel_path -vvv
-      - name: Check out repo
-        uses: actions/checkout@v3
+        run: bash packaging/install_torchcodec_wheel.sh
+
+      - name: Install ffmpeg, post build
+        run: bash packaging/install_ffmpeg.sh ${{ matrix.ffmpeg-version-for-tests }}
+
+      - name: Install test dependencies
+        run: bash packaging/install_test_dependencies.sh
 
       - name: Run generation reference resources
         run: |